Renewable energy sources such as solar, wind, wave, falling water, and biomass wastes have tremendous potential as being main energy sources, but currently suffer from a variety of problems that prohibit their widespread adoption. For example, utilizing renewable energy sources in the production of electricity is dependent on the availability of the sources, which can be intermittent. Solar energy is limited by the sun's availability (i.e., daytime only), wind energy is limited by the variability of wind, falling water energy is limited by droughts, and biomass is limited by seasonal variances, among other things. Because of these and other factors, much of the energy from renewable sources, captured or not captured, tends to be wasted.
These inefficiencies in capturing and saving energy limit the growth of renewable energy sources into viable energy providers for many regions of the world, because they often lead to high costs of producing energy using the renewable energy sources. Thus, the world continues to rely on oil and other fossil fuels as major energy sources because of more than a century of government subsidization for infrastructure and technology developments that make it deceptively convenient and seemingly inexpensive for the present generation to expend fossil reserves for production of usable energy. Exploitation of finite fossil and fissionable fuel reserves provides a false sense of value because the replacement cost for the resource expended and the cost of environmental degradation along with the health impacts that are incurred are not included in the purchase price for such energy.
Surplus electricity, particularly power from large coal- and nuclear-fueled central power plants presents hidden costs including related environmental pollution problems of prompt production of toxic emissions of heavy metal residues and greenhouse gases from fossil fuel combustion along with requirements for expensive long-term storage of radioactive wastes. Large expenses for capital equipment, maintenance, and fuel costs to provide sufficient capacity to meet customer demands are incurred in present utility power distribution systems.
These and other problems exist with respect to the sustainable production and utilization of renewable resources.